APRIL, 1906.] THE ORCHID REVIEW. 101 
And the reverse of course might take place. The limits of crossing were 
partly determined by systematic affinity, but within those limits certain 
physiological and perhaps mechanical difficulties could be traced. The 
subject was highly interesting for several reasons, and the botanist could 
not ignore hybrids if he wished, for they occurred in nature, and in some 
groups were quite common, for example Salix, Epilobium, and Odonto- 
glossum, and a good many cases had been proved experimentally. Hybrid- 
isation was largely a question of opportunity. Wherever species that would 
cross grew together hybrids might occur, and as Orchids were so largely 
dependent upon insects or fertilisation, and insects did not confine their 
visits to one species of flower, the pollen was sure to get mixed, and hybrids 
would result. Hybridists carried the matter further by making crosses 
which could not occur in nature. It was not always possible to state with 
certainty whether a given plant was a hybrid or not without knowing its 
history, not even by tracing resemblances, though this method was 
generally sufficient when the history of an importation was known. In 
conclusion he pleaded that hybridists might do more to prove the origin of 
suspected hybrids by direct experiment. The common Odontoglossum xX 
Andersonianum had not yet been raised artificially, though there could be 
no doubt as to its origin. 
Mr. Thwaites, Streatham, who contributed some interesting observa- 
tions, remarked that he had succeeded in raising seedlings between Soph- 
ronitis grandiflora and Brassavola Digbyana, using the former as the pollen 
parent, but the seedlings had not yet flowered. He also advocated dividing 
the pollinia if larger than that of the species used as the seed parent, 
otherwise the pollinia were liable to choke the style passage, and thus 
result in failure. 
Further remarks were made by Mr. Watson, of Kew, Mr. William 
Marshall, Mr. C. T. Druery, Mr. Bunyard, jun., Mr. H. Little, and Mr. 
H. J. Veitch, the latter describing the evening as one of the best and most 
instructive that he had spent at the club. The meeting concluded with a 
hearty vote of thanks to Mr. Cookson and Mr. Chapman, on the motion of 
Sir John T. D. Llewelyn. 
ORCHIDS AT KEW. 
As the season advances the number of Orchids in flower tends to increase, 
and a long list could again be cet of those now flowering at Kew. 
In the Warm house the D bi are still pi though con- 
siderably diminished in numbers, prominent among them being several 
good forms of D. crassinode, D. — var. giganteum, D. lituiflorum, 
li the well-known D. thyrsifl carrying six veniiebens 
Ae 3 
